This invention relates to the packaging of dry particulate foods such as ready-to-eat (xe2x80x9cRTExe2x80x9d) cereal. More specifically, this invention relates to production of bagin-a-box cartons using induction heating.
Cartons for dry particulate products such as RTE cereal are usually formed from a blank of paperboard or similar material comprising sidewalls with top and bottom flaps. The liner is a plastic or coated paper bag to preserve the particulate product. The liner can be filled and sealed before or after being placed inside an open carton, the flaps of which are then folded and sealed.
In U.S. patent application Ser. No. 09/213,100 filed Dec. 17, 1998, the use of induction heating and a vacuum is disclosed to seal a filled and sealed liner along weakened seal or tear lines without breaking the seal of the liner to a dispensing panel or door forming a dispensing opening. The present application is directed to other applications of the technology described in the ""100 application to prepare alternative containers and other products, including, e.g., single-serving type containers.
The present invention is directed towards a method for affixing filled and sealed liner bags in bag-in-box cartons wherein the liner is filled and sealed before being inserted into the carton and is thereafter induction sealed to the interior of the carton without breaking the seal of the liner. The carton may be open or sealed when the liner is adhered to the carton interior. Preferably a weakened tear line is formed in the liner corresponding to a pour spout or opening of the carton so that upon initial opening, the liner separates from the reminder of the liner along the weakened tear line to provide access to the contents of the carton.
Cartons made according to the invention have a filled and sealed liner which contacts an adhesive that is activated in situ by induction heating, preferably under vacuum, such that the liner adheres to the interior of the carton or a selected portion or portions thereof without breaking the seal of the liner.
The present invention is also directed to single serving xe2x80x9cbag-in-bowlxe2x80x9d containers, having a filled and sealed bag that is adhesively bonded to a rim or peripheral edge of a disposable bowl made of paper, cardboard or plastic. The bag-in-bowl is made in a manner similar to the process described above in that it relies on induction heating to bond the bag to the bowl using a heat activated adhesive without breaking the seal of the bag.